


Superbat Week 2019

by Behind_The_Hood



Category: Batman - All Media Types, Justice League - All Media Types, Superman - All Media Types
Genre: Alternate Universe - High School, Alternate Universe - Merpeople, Body Swap, Jealousy, M/M, Parenthood, Possessive Behavior, Red Kryptonite, Space Jail, Teenagers
Language: English
Status: Completed
Published: 2019-07-25
Updated: 2019-08-01
Packaged: 2020-07-19 15:41:36
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 7
Words: 3,760
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/19976494
Author URL: https://archiveofourown.org/users/Behind_The_Hood/pseuds/Behind_The_Hood
Summary: Day 1: KryptoniteDay 2: PossessiveDay 3: Heat Vision & UndercoverDay 4: Bed SharingDay 5: Mer AU & On a MissionDay 6: Swapped RolesDay 7: Trapped Together





	1. Kryptonite

Bruce walks down the deserted halls, huge and hallow and haunting without the student body to breathe life into it. He’d come in late today on purpose, hoping to avoid the other students. The header of every newspaper and news station this morning is reporting the succession of Wayne enterprises after his graduation.

These people only ever liked him for his name before, now they’d be like bees to honey trying to get his money too. He can only trust two people in this school: Oliver, who has his own money and company to inherit, and Hal, who has a promising career in the Air Force lined up after he graduates. They like Bruce for the person he is, not _who_ he is or _how much_ he’s worth. Even if Hal calling him Spooky can get annoying at times.

Bruce closes his locker door and turns around, only to find himself staring into gorgeous blue eyes.

Bruce comes to a quick halt so he doesn’t slam into the guy, eyes wide.

Muscular arms come over his shoulders and trap him against the lockers. He stares into the blue eyes sparkling down at him. If Bruce wasn’t sure he was imagining it, he’d swear Clark’s eyes were almost glowing red.

Bruce leans away from him, brows furrowing. Clark only leans closer.

He’s smirking. “Hi, Bruce.”

Clark has never given Bruce the time of day before, always caught up in his classwork or football. He’s here on a scholarship; Bruce would expect nothing less. Still, he’s one of the few people in the school to do so. Bruce has had a crush on him for a while now, and any other day, Bruce would be over the moon to have Clark talking to him, being this close to him, giving him this type of attention.

But this isn’t how Clark normally behaves; he’s clumsy and stuttering and awkward. And the timing is…too coincidental to be a coincidence.

Bruce frowns and turns his head away. He’d thought Clark was above doing something like this. “What do you want, Clark?”

A hand cups his cheek, and turns Bruce’s face back up to meet his. Clark’s class ring reflects a gleaming red against his blue eyes. “You,” he says simply.

Bruce glares, then ducks under his arm and makes his way down the hall. His mood is significantly worse off now than it had been when he woke up this morning. He can’t believe he was so wrong about Clark’s character. “Leave me alone, Clark.”

Clark doesn’t follow after him, and Bruce hopes he got the message.

* * *

He didn’t.

Everyday, Clark is waiting for him at his locker, whether Bruce shows up early or late. He follows Bruce around during gym. He walks him out to his limo when Alfred shows up after school.

If they were dating, he might have enjoyed it more.

And what’s worse is that Clark isn’t the only one, he’s just the most persistent. Bruce has found love letters in his locker, flowers on his desks, several girls waiting outside the doors to ambush him after school—Clark is at least a buffer against them—and he’s tired of it all. If his claiming CEO of Wayne Enterprises wasn’t contingent on him graduating, he’d drop out and claim his position now.

As it is, he still has over half a year left, and Clark’s interest doesn’t seem to be waning.

* * *

Bruce grits his teeth, his jaw muscles— _all_ his muscles—tense. Clark smiles, eyes teasing, as he leans close enough that Bruce can feel their lips ghosting together. He’s as close to the wall he can get without phasing through it. Bruce’s eyes narrow when Clark comes a pinch closer still. “How much?”

Clark pauses, his smile falling, and he leans out of Bruce’s space enough that he feels like he can breathe again. “How much?”

Bruce is full-on glaring now. “Money. How much to make this stop?”

A smirk creeps back onto Clark’s lips, and he leans closer once again. He expects Clark to whisper his price against his lips; instead Clark’s ring is cold against Bruce’s skin when he puts his hand against his neck, tilting Bruce’s head up just so. His eyes sparkle. “I’ve never wanted your money, Bruce. I want _you_.”

Bruce’s breath catches when Clark closes the last bit of space between them.


	2. Possessive

He shouldn’t feel this way about the Brucie persona. He’s known it was an act since Batman first revealed himself. He’s known every man and woman hanging off Brucie’s arm was just a cover, and that other than Selina and Silver, there was never any feeling behind it.

He knows Selina only flirts with Bruce anymore because it gets a rise out of him, and she is nothing if not a tease, no matter that the target is outside the building, floating and glaring red eyes down at her. She smiles through the window, and sends him a wink as her hand slides down to grab Bruce’s—

“Superman,” Diana signals.

Time’s up.

He flies off, because he still has a job of his own. And he’d like to get it done quickly.

* * *

Bruce smiles as Lex manages to run Selina off—or so he believes. Bruce takes a sip of his ginger ale and eyes Lex over the rim of his glass. It’s appraising, but he’s sure Lex sees it more for lust. That was the point. He hadn’t subtly lured him across the room for nothing.

Lex takes the glass from his fingers—Bruce pouts at this—and sets it on a passing waiter’s tray. “You know, Bruce, it’s been a long time since we’ve gotten together and—” his eyes rove down Bruce’s form, then meet his gaze again, and he smirks. “Talked.”

Bruce takes a step closer, so they’re chest to chest. Nearly nose to nose. Almost lip to lip. And whispers, a breath away, “Last I remember, there wasn’t much talking.”

A hand comes to his hip, fingers gentle, then gripping. Lex chuckles, keeping the distance between them. “I believe you’re right. But was that so bad?”

Bruce smirks now, stepping away. His fingers wrap around Lex’s tie, pulling him along. “It could’ve been better.”

* * *

Cyborg walks away with a copy of the files they need, backing it up to the Watchtower for safe keeping, and Superman is free to return to Gotham. Bruce doesn’t need to distract Luthor anymore.

He follows his heartbeat. Second floor; private room. Away from the party. He finds him bidding Luthor a goodnight, voice sounding a little breathless.

Superman clenches his fists.

He’s through the window as soon as the door clicks shut, and on Bruce before he can even turn around. His arms are tight around him, body flush to every inch of Bruce’s. “I hate when you play Honeypot.”

Bruce laughs, pressing his forehead to the wood of the door. “Honeydick.”

“Not from what I heard.”

Bruce laughs again, amused with Superman’s apparent pouting, and he turns in the cage of Superman’s arms. “I didn’t have sex with him. You know that.”

He does know that. He didn’t like hearing the panting and petting though. He puts his head to Bruce’s shoulder, his arms lowering so he can hold Bruce’s hips.

Bruce’s fingers card into his hair.

He kisses his shoulder, then again. He moves to Bruce’s neck—clear of any marks, thankfully—and puts his lips there. He leaves them, waiting, and when Bruce tilts his head back, he sucks a hickie just above where his suit collar rests.

Bruce’s fingers curl; his heart rate picks up.

* * *

It isn’t until much later that Bruce returns to the party, looking more debauched than when he’d left. And Lex nearly chokes on his drink when he sees the unkempt suit and mussed hair. The hickies on his neck.


	3. Heat Vision & Undercover

Bruce swipes the card through the door’s lock, presses in the code, then does an iris scan. The door opens and Clark walks through it with him. It may work on Kara, but blond isn’t his color. “Contacts?”

Bruce gives a nod.

They walk at a leisure pace, looking like just another two custodians for LexCorp. When they reach the blind spot Bruce set up, they shed the janitor coveralls and drag on the lab coats hidden in the trashcan. “We have a twelve minute loop on the feed. Any more than that and someone will get suspicious,” Bruce whispers, pulling the beard off his face and putting on glasses.

Clark trades his blond wig for a brunette one and a mustache. He still looks ridiculous.

“And how did you get these cards?”

“The true owners are indisposed at the moment.”

Bruce offers his other iris this time, with a different contact to match the scientist he’d seen coming down this elevator for the past two weeks. It checks out and the doors slide open for them. They have to swipe their cards again before they can go down.

“Cyborg said sixteen,” he hears Clark mutter as he presses the button.

There’s no elevator music, so they stand in stony silence for the ride. And when their floor is reached, nobody seems to be around. Not that Clark can see at least. “There are lead lined cylinders that way.” He nods his head to the left.

So Bruce follows Clark’s lead down the hall, then the stairs where he’d had blocks in his vision. The cylinders aren’t what they expected to find down here, but they pause when they come upon them all the same.

Malformed humans, globs that might _once_ have been humans, and then one, at the very end of the line, that is a perfectly formed baby; maybe a year old.

“Conner,” Bruce reads the label.

The baby’s eyes blink open then, and stare at them, through them. It’s unnerving. Then it begins to cry in its tank.

Then its eyes turn red.

“Shi—” The sound of glass breaking rings sharp through the room, and Clark moves Bruce out of the way just before the heat vision burns holes through his head. He goes back for the baby.

Conner keeps crying, and his vision is still red hot and shooting from his eyes, but now he’s cradled in Clark’s arms with Clark’s hand over his eyes. Clark looks close to panicking.

Bruce touches his earpiece. “I think we found it…”

* * *

Sneaking a wailing baby with glowing eyes out of LexCorp proves more of a challenge than they had anticipated this trip being. Clark ends up having to move himself and the baby so fast that they’re invisible to the naked eye.

Bruce walks them back out, up the elevator, and changes back into his coveralls and beard. Their time is still running so they walk out the way they came. If Clark moves too quickly while vibrating, he’ll leave a blur on camera. Conner is still whimpering in Clark’s arms, but it’s better than wailing.

* * *

“It’s Kryptonian DNA,” Bruce says, arms folded. “ _Yours_ , specifically.”

The Fortress had been helpful in discovering this.

“There’s also human DNA though,” he mutters. Looking through the numbers and words on the screen used to be impossible—and sometimes he will come across a word he doesn’t recognize—so learning Kryptonian seemed useful. It was.

“Whose DNA?” Clark asks, coming to join his side.

Conner is being held Kelex, and staring at the room around him as though he were taking in the space and memorizing it. He may very well be.

“Well, if I had to take a _wild_ guess,” Bruce implies flatly, casting his eyes to Clark’s.

Clark is still staring at the screen, then pulls a face, his disgust clear.

Bruce narrows his eyes. “It isn’t Conner’s fault.”

Clark looks at him, trying to control his features. And failing. “I know that.” His voice wavers.

“Whether you like it or not,” Bruce continues, unrelenting. “That boy is your son.”

Conner’s eyes turn to them, all too knowing.

Clark’s face is pinched in anxiety as he looks back at Conner. Bruce takes his hand. “But you don’t have to raise him alone, Clark.”

Clark doesn’t look at him. He squeezes Bruce’s hand though, then folds their fingers together. “Thank you.”


	4. Bed Sharing

They stand shoulder to shoulder, staring, as the diplomat tells them how thankful they are that the Justice League sent two of its best to help solve their war crisis.

Superman mutters some response, but their eyes stay frozen.

They bid them a good night. The diplomat leaves after that, closing the door behind themselves.

Superman breaks the silence between them first, clearing his throat. “Uh, so. They thought we were a couple.”

Batman nods. “At least it’s a big bed.”

Superman gives a little laugh. “Better than the first time we had to share a bed, huh?”

Batman hums, and turns his face away. If he’d known then how important Clark would be to him now…

Superman claps his hands. “Welp, guess we should hit the hay.”

“Some part of you never left Kansas, did it?” Batman mutters.

He earns another laugh for his effort. They don’t have a couch for one of them to sleep on or chairs to shove together, so they crawl into the bed, and keep a decent gap from each other.

It shouldn’t be as hard to sleep as it is, but Batman ends up staying awake for over half the night. He listens to Superman beside him, his slow breathing. He’s been steadily shifting closer.

Superman moves a lot in his sleep.

When Batman finally gets to sleep, it’s for hardly more than two hours. Everything about him feels heavy. He tries to move and get out of bed. It’s then that he feels the arm around his waist, the thighs pressing to his own, the hand keeping him from moving away from the chest at his back.

His heart thumps heavy, and he hopes Superman is too deep in sleep to have noticed.

“Bruce?” Of course not. His voice is groggy and thick with sleep. “What happened?” he asks.

He feels Superman go very still behind him as he realizes their position, then he isn’t there at all.

“I’m so sorry!”

Batman rolls onto his back, eyes on the arched ceiling high above their heads. “It’s fine. You were asleep.”

Superman has moved back to his side of the bed now, and looks more than embarrassed.

“It’s not like waking up cuddling with someone is the worst thing in the world, Superman,” he assures him. Batman rolls onto his side again, his back to Superman.

He hears Superman shifting around behind him, and closes his eyes.

“So,” Superman says, hesitating. “It was okay?”

Why couldn’t he just let it go? “It was fine, Superman. Don’t worry about it,” he says.

It’s quiet for another moment, then, “So, it would be okay to do it again?”

Bruce turns around and looks into Superman’s nervous eyes.


	5. Mer AU & On a Mission

**Notes for the Chapter:**

> I was on anesthesia and a Norco yesterday and totally forgot to post this chapter. I am SO sorry.

To say that the mermen are huge would definitely be an understatement. Held down flat on their stomachs through the magic of Arthur's trident, they are easily double the size of a bus. All black scales, flicking tails, eyes near to glowing; they look like angry cats. All five of them.

“And you think they’re the ones who’ve been attacking Atlantis?” Clark asks.

“I know they are.” Arthur congers up images around the water that shows the mermen throwing themselves at the protective walls surrounding Atlantis.

Diana frowns. “But why? What reason do they have? They are not Trenchers; they must have a motive.”

The largest one among them makes a sound like a growl; a deep rumble from deep in his chest.

Clark swims to stand in front of him, his glowing eyes following Clark’s movements. He’s dark from the top of his head all the way to the tip of his tail, they all are. They have dark hair as well, except one, who has a strip of white at the front. Their irises are the only thing with a touch of color, a shining blue.

His growling only continues as Clark grows closer. “Can you speak?”

His growling trails off, and Clark can see the eyes reassessing him. He feels less like prey, and more like an enemy under that glowing gaze. The merman clicks at him, rolls his tongue, whistles.

“They can speak,” Arthur says. “But it is no language we would know.”

Clark frowns. The merman copies.

His eyebrows raise in surprise. The merman copies that action as well.

“Hey, Arthur,” he calls over, and the merman tilts his head as Clark had. “He’s mimicking me.”

“What?” Arthur swims over, and watches as Clark tilts his head again. And the merman copies. “I’ve never seen them do this before. They usually seclude themselves away in some cave and keep to themselves.” He frowns, looking between them all. “This is odd.”

“So it started with unprovoked attacks, and now their behavior is changing?” Victor asks, joining them. Diana and Hal follow. Victor’s eye scans over the one in front of them. The growling starts again, blue eyes on Victor. “I don’t see anything that sticks out.”

The one with the white strip of hair thrashes suddenly, hissing at them.

“Wait,” Arthur says, then swims off, leaving them with the aggressive and dangerous mermen.

One slightly bigger than the smallest yips at the hissing one, and he slumps, only growling now. Arthur is gone for easily twenty minutes, and Clark entertains himself by having the biggest merman mimic his movements and expressions. Interestingly enough, he won’t smile.

“One is missing,” he says upon his return. “The elder of their group.”

“Could they be looking for him?” Diana asks. “Could that be why they’re attacking Atlantis? They think he’s there?”

Arthur frowns, then looks at the biggest merman. “They wouldn’t attack at all unless they knew for sure. They’re creatures of stealth. Master hunters.”

“Then we need to go back to Atlantis and find him.” Hal nods, like it’s that easy.

“It isn’t that easy,” Arthur argues. “I would need to evacuate the city first, and they would need to not destroy every building in sight with either their size or their wrath at whoever took him.”

Clark frowns. “What makes you think he was taken?”

“He never leaves the cave. He tends to their wounds and keeps their home safe from intruders. He wouldn’t have left, not even voluntarily.” Arthur motions everyone back. “They trust you most Clark; you’ll have to keep them under control.”

“That is a terrible idea,” he mutters, looking into glowing blue eyes, trained on him.

Arthur either doesn’t hear or doesn’t care, because he releases them all, one by one. When they don’t immediately attack him, he takes it as a good sign.

He brings a hand to his chest. “Clark.” Then swims closer, and puts a daring hand to the biggest one’s chest.

He stares at Clark’s hand, a rumble not quite like his growl coming from his chest.

Clark tries again. “Clark.”

The merman puts his hand to his own chest now, and a whistle leaves his lips.

Clark smiles. Progress.


	6. Swapped Roles

“You seem oddly pleased about this, Alfred,” Clark comments as he limps Bruce’s body into a med-bay bed.

“Not at your expense, I assure you,” he says, helping Clark lay out. “But Master Bruce hardly lets me tend to his injuries the way they should be. You will, however.” He smiles, and Clark feels like some of it _is_ at his expense.

Bruce floats over, so he’s lined his body up over Clark’s. His own. Who cares. He’s tired of this happening. “I’ll keep an eye on Metropolis while they look for Mr. Mxyzptlk.”

Luthor is still running loose through the streets, looking for him. Mr. Mxyzptlk showed up out of the blue and said he could solve all of Superman’s problems. And now he’s in Bruce’s body _again_ , and Bruce is going to have to go out and fight Luthor for him. At least the change in fighting style will throw the billionaire off his game.

“Be careful of his kryptonite knuckles,” Clark warns.

Bruce kisses him. “I’ll be fine. Alfred will take care of you.”

“It really hurt,” he whispers, brows drawing together.

Bruce brings a hand to his cheek. “I know. Believe me, I know. Alfred knows what he’s doing.”

He gives Clark one more kiss, and then he flies off. Clark’s almost jealous of how quickly Bruce caught a grasp of his powers when Clark took years learning how to handle them all. But that’s what Bruce does. He adapts better than anyone else Clark knows. Nothing ever stops him.

With a mix of humor and horror, he thinks that even death has never stopped Bruce before.

So Alfred hooks him to an IV drip, puts an oxygen mask over his face, and lets Clark sleep away the pain.


	7. Trapped Together

**Notes for the Chapter:**

> I apologize, again, for having a late chapter. My medicine has absolutely kicked my butt.

Superman blinks, bored out of his mind. Beside him, Batman has his face buried in his hands. The metal bench under them is perpetually cold, even through their suits.

A guard walks by once more, patrolling his charges.

Trespassing.

They’d been booked in for trespassing.

Around them, the jailhouse is alive with cursing and spitting, angry aliens claiming their innocence or shouting obscenities at the guards and each other.

The laser bars to their cell have no effect on Bruce, passed tickling his skin, they’d found out, but Clark had nearly blacked out from the pain when he'd tried to walk through them. They didn’t know what the lasers were, but they decided to call Diana and wait out their bail.

It was an asteroid belt. They’d passed over it on their way to the distress signal, but had to go through it on their way back for the ships leaving over their head.

The asteroid belt was, apparently, private property. And its owner was not pleased with their arrival.

And now they sit, and they wait.

Neither of them is truly to blame for it either, so they can’t even bicker among themselves.

Bruce sighs and leans back, putting his head to the wall. Then he turns to look at Clark. “How’s your hand?”

Physically, there was no visible problem, but passed the visibility, “I think my blood has stopped boiling.”

Bruce’s lips purse, eyes on Clark's hand.

The buzzing of their laser bars stop, and they look over to see a guard with Diana at his side. Her hands are on her hips, and she’s frowning at them. “I left you alone for two days.”


End file.
